Charging (In)Efficiency

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insightman said:
As a doctor, I'm sure you realize that there's never enough time in a day, which is what makes time so valuable. You absolutely want at least a 32-Amp L2 EVSE because you don't want to wait any longer than necessary for your SE to be ready to drive again.

It's not just the charging speed that tips the balance in favor of L2. When it's cold or hot outside, you will likely want to be pre-conditioning the interior of your SE, and this process is less problematic with an L2 EVSE. If you try to pre-condition your SE's interior while L1 charging, it can limit charging, leaving you with a comfy interior but less than a full charge.

Even if you have a second car that could get you to your destination while your SE is L1 charging, you'll start regretting that the second car (even a Tesla, Taycan, or Corvette) is depriving you of the fun you could have had in your SE. That's my completely unbiased opinion :)
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Good copy on all counts!! Man, I love this forum -- hopefully I won't forget everything I've learned here! I'm pretty sure I'll go with the L2 once I've seen how L1 performs. In the Bay Area where I live temps don't get too crazy, and it will remain in the garage for all charging, but I still want the best efficiency.

Dang Omicron is crushing everyone in healthcare, but my Mini musings are helping to keep my spirits up. Hoping to see a downward trend in the coming weeks. Cheers, all!
 
I have the car set to charge immediately and to pre-condition for departure at 6:45 AM M-F. My wife gets home between 3 and 4 typically with 60% SOC still. The car is done with primary charging by 8 or 9 pm.

Does the charging report in the app also count energy added after the primary charge? I presume that over the 10+ hours until it is unplugged, it periodically adds some juice to counter passive losses. Then then in the morning when it is conditioning. Does the report for that charging session count all of that? Everything it takes from plug-in to plug-out (whether that is the next morning or several days)? If it isn't driven on a day, that "session" could include the main charge to 100%, a couple of days of passive losses plus a few sessions of conditioning.

Rob
 
AndysComputer said:
Then I guess the battery temperature isn't important for the rate an L2 charger can pump those electrons in, only DC fast charging.
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I would say it’s important for charge and discharge, hence why power is significantly reduced during cold weather (80% at 20*D, 60% at 0*F (anecdotal)).
 
I would have traded my RAV4 Hybrid (which we love) for a Prime if I could have gotten one at MSRP at all. They don't (or didn't) officially sell them in Washington for some reason, even the though State is nuts for EVs. Now that I have the Mini SE also, I wouldn't do it.

Rob
 
Urbanengineer said:
I would say it’s important for charge and discharge, hence why power is significantly reduced during cold weather (80% at 20*D, 60% at 0*F (anecdotal)).
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I just completed a highway round trip at -10F. Whopping 65 mile range. I would have been sweating over the 4 mile remaining range it was screaming at me, except I was freezing in G+ mode!
 
Teddydogno1 said:
Does the charging report in the app also count energy added after the primary charge? I presume that over the 10+ hours until it is unplugged, it periodically adds some juice to counter passive losses.
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My EVSE shows no change in the amount of kWh consumed after charging finishes. ie when the car is just sitting there plugged in so losses while parked seem immeasurably low. The EVSE consumption counter registers down to 10wattHours resolution so 0.01 kWh and it never goes up. The longest we’ve had the car parked up after charging finished is 3 days and the counter never moved…
Our Tesla also doesn’t seem to pull any but will begin charging again once it has dropped by 1% below target charge level which seems to be every few days.
 
insightman said:
As a doctor, I'm sure you realize that there's never enough time in a day, which is what makes time so valuable. You absolutely want at least a 32-Amp L2 EVSE because you don't want to wait any longer than necessary for your SE to be ready to drive again.

It's not just the charging speed that tips the balance in favor of L2. When it's cold or hot outside, you will likely want to be pre-conditioning the interior of your SE, and this process is less problematic with an L2 EVSE. If you try to pre-condition your SE's interior while L1 charging, it can limit charging, leaving you with a comfy interior but less than a full charge.

Even if you have a second car that could get you to your destination while your SE is L1 charging, you'll start regretting that the second car (even a Tesla, Taycan, or Corvette) is depriving you of the fun you could have had in your SE. That's my completely unbiased opinion :)
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I agree. Even if the pennies don't merit L2, the experience does. Getting a full charge in under 4 hours without thinking about it is one of the best parts of owning an EV, IMO. I'd enjoy ownership a lot less if I had to plan my driving around 12+ hours of charging.
 
Installing an L2 EVSE might make it on to my to-do list this spring. Too cold right now to be climbing around in the attic. What's the most the MINI draws? 24A?
 
chrunck said:
Installing an L2 EVSE might make it on to my to-do list this spring. Too cold right now to be climbing around in the attic. What's the most the MINI draws? 24A?
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Too cold sounds like the opposite problem I usually have in attics! I don't think I've ever not been sweaty afterwards. Wrestling the giant 6awg cable around was definitely enough to keep me warm when I did mine
 
I think the SE's onboard charger maxes out at 7.4kW (and almost 11kW for 3 phase) so if that's the case 7400W/240V is ~ 30.83A. Could be helpful if you place the EVSE in a location that can charge both inside and outside the garage. The 25 ft cable is more like 19 feet actual (3 ft to the floor and 3ft back to the charger port). No problem for a MINI but something to consider for households with 2+ EVs.
 
F14Scott said:
I agree. Even if the pennies don't merit L2, the experience does. Getting a full charge in under 4 hours without thinking about it is one of the best parts of owning an EV, IMO. I'd enjoy ownership a lot less if I had to plan my driving around 12+ hours of charging.
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Totally. Heck, in addition to faster (and more efficient) charging one of the things I’m looking forward to most once I have my L2 EVSE installed is just eliminating the need to pull the OEM charging cable that came with the car out of the boot ;) and stowing it back in there every time I want to plug in.

A real first-world “problem,” for sure! But I’m all for the enhanced experience I expect an L2 to provide. (And while I have no plans to move, having the wiring work done — by a pro, too — can’t hurt my home’s resale value, either.)
 
wessy said:
And while I have no plans to move, having the wiring work done — by a pro, too — can’t hurt my home’s resale value, either.
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I consider adding L2 charging to be a home improvement. In a couple years that will become a big selling point on homes, if the current adoption rate of EVs continues.

And having it done by an electrician may be advantageous for insurance purposes in the case of a garage fire. Not to mention there's the federal tax credit that can pay for a significant portion of the install.
 
I believe the US Alternative Fuel Infrastructure Tax Credit is expired as of December 31, 2021, but check with your city/state and utility provider for incentives/rebates!
 
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teslarati97 said:
I believe the US Alternative Fuel Infrastructure Tax Credit is expired as of December 31, 2021, but check with your city/state and utility provider for incentives/rebates!
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I just received notice that I was denied the rebate offered by my utility. Why? The charger I installed was not "permanent". Fap!
 
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